ES300 P0135 O2 Oxygen Air/Fuel Ratio Sensor
12-28-06, 08:03 PM
#1
Driver School Candidate
Thread Starter
ES300 P0135 O2 Oxygen Air/Fuel Ratio Sensor
A couple of weeks ago, the check engine light lit up on a 1997 ES300 that we own. I thought to myself, here is an opportunity to learn something new perhaps. I’ve always enjoyed working on our cars and try to do most of the maintenance and repair myself. So, I was more than eager to tackle this problem.
Getting the error code…
A couple of days later, I took the car to AutoZone and they read the error code for me free of charge. They do this as a courtesy and betting that once you know the cause you may buy any malfunctioning sensors from them. So, even though I wasn’t sure if I wanted to try to fix it myself, I figured if I knew what the problem was then I would know what to expect when I took my car to the shop.
Anyway, the error code was P0135 indicating that the heated oxygen sensor 1 on bank 1 was not functioning properly. After reading the code, the guy at AutoZone offered to show me exactly where the sensor was and I accepted his offer. So we popped up the hood and he said “That’s it! Right there!” pointing to the O2 sensor on the exhaust manifold between the radiator and the engine. (You’ll see later that the sensor he showed me was for bank 2 and not bank 1.) After we walked back into the store to print out the error code, he also looked up the price on the O2 sensor and it was around $118 for a Bosch sensor. I thought to myself, that sounds reasonable, but I wasn’t ready to buy the part yet. I thanked him for his help and drove back home to do my research.
O2 Sensor vs Air/Fuel Ratio sensor...
As far as I know only the California models use the Air/Fuel Ratio sensor. No, the O2 sensor is not the same as the Air/Fuel Ratio sensor. The O2 sensor provides a simple too lean or too rich information to the ECM. It acts like a switch it either swings the lean or the rich way and operates in a narrow range. The boundary between the lean and rich condition represents the ideal air/fuel ratio of 14.7:1. The ECM therefore constantly adjusts the air/fuel ratio by a very small amount back and forth to stay at this ideal boundary. The air/fuel ratio sensor on the other hand operates over a wider range and provides a more accurate near linear voltage representing the amount of oxygen in the exhaust. Therefore, with an Air/Fuel Ratio sensor the ECM is able to more precisely control the air/fuel ratio. Also, the Air/Fuel ratio sensors operate at a higher temperature around 1200F (650C), whereas the O2 sensors operate around 750F (400C). And, yes the Air/fuel ratio sensors do cost more, roughtly about 40% to 50% more.
Locating the O2 sensors…
After doing a little search on this site, I found out that my 1997 ES300 has three O2 sensors, sensor 1 bank 1 is located right after the exhaust manifold close to the firewall, sensor 1 bank 2 is right after the exhaust manifold by the radiator, and finally the downstream O2 sensor is located on the exhaust pipe after the catalytic converter underneath and toward the center of the car. Sensor 1 bank 1 is the hardest to find and get access to, but with a shop light and a little persistence I was able to find it. There is really no easy way to get to it though because it’s sort of sandwiched deep down below, between the firewall and the back side of the engine. But, I will tell you later how I got to it.
Buying the O2 sensors…
I know that everybody has his or her opinion on this, but I like to buy factory and OEM parts for most repairs, unless it’s an expensive part and the price differential between the OEM and the after market part is too much. Fortunately, with a little bit of online search I was able to find the O2 sensor (part number 89465-33180 superseded by 89465-06100) from an out of state Lexus dealer for about the same price (whole sale price) as what AutoZone wanted for their Bosch part. The catch was that I had to order the part online from their site to get that price. This was hard to believe! The OEM Lexus part cost the same as the Bosch part from AutoZone? My local dealer had quoted me close to twice that price on the phone. I knew that I had struck gold. At that price, I went ahead and ordered two of them. I figured at 120K miles, the other sensor is probably on its last leg out anyway. Now, when I ordered the part form Lexus, I had to specify whether I wanted the front or rear sensor. The front (upstream) sensor is the one used for sensor 1 on bank 1 and bank2. The rear sensor (89465-06020) is the downstream sensor after the catalytic converter, which I elected to not replace.
Replacing the O2 sensors…
OK, now I have the parts but will I be able to finish the job. Truthfully, before I ordered the parts, I spent about an hour locating the sensors on the engine and deciding how I could get to them. The O2 sensor on the exhaust manifold of bank 2 is by the radiator, sticks out like a sore thumb, and is pretty easy to get to. The bank 1 O2 sensor is however a totally different story. After a long few minutes of looking around with the shop light I spotted the sensor on bank 1, but I could see that there was no way I could get to it from the top of the engine without removing the intake manifold. So I put the car on ramps and got under the car to take a look. Again, I was able to see it from underneath the car but I was having trouble getting my hand through the cracks between the parts and reach it. After laying on my back under the car for a while and wondering why in the heck I am doing this, suddenly I saw a way from behind the suspension cross member that I thought I could drop a socket on the sensor. Well I thought I’m half way there, but the sensor connector was another 10 inches or so higher on the side of the engine and I could not get my hand or fingers through to reach it. There were two problems. First I had to unlatch the tab on the side of the old connector and disconnect it. Second, I had to be able to insert the connector of the new sensor into its place. After scratching my head for a while (kind of tough to do while you’re under the car on your back), I thought I could perhaps use a long flat head screw driver with a narrow blade to undo the latch with one hand and then tug on the wires with the fingers on my other hand to pull the connector out. Well, why not. I thought it would work. Now, I needed a way to be able to lift the connector of the new sensor and to guide it into the mating connector on the side of the engine. For this I needed to build an SST (Special Service Tool). While looking around the garage, I found a spiral looking wire in the trash can which had a glass butterfly on it. I think it was something that you stick in a plant pot. My wife had thrown it away and it seemed to be just what I needed for my SST. I was thinking about using a wire hanger but I could not find one around the house (all the ones we had were plastic), and this thing whatever it was seemed to be perfect for the job. So using pliers I formed the end of the wire into a three-sided square (is that possible?), leaving one side open to get the square around the neck of the connector. I made it just the right size so that I could easily get it around the lower and smaller part of the connector. Now, I could use this to lift the connector and place it in position but my SST wire would be too flimsy to push the connector in. This wasn’t too big of a deal because once the connector was in place I could then use a long screw driver to push the connector in.
The tools for the job…
Here are some pictures of the tools that I used.
I got the O2 sensor socket from AutoZone. It’s a special deep socket with a slit (opening) on the side. The wire at the end of the sensor can be bent down gently and routed through this slit so that it doesn’t get crushed by the end of the socket. I could have bought this socket for around $11, but I got it from AutoZone on a loaner basis. I could return it when I was done for a full return of my deposit. However, I think that I am going to just keep it.
Replacing the O2 sensors…
First of all, I disconnected the negative cable from the battery and tucked it away. I’ve read that if you don’t, there is a remote possibility that the airbags could get deployed while you are working on the car. This could result in possible injuries and at the very least would cost a lot of money to fix. I replaced the sensor on bank 2 first, since it was the easier one to get to. It didn’t take much force to loosen the sensor. However, after about half a turn, the sensor would not turn any more no matter how much force I applied. It seemed as if there was some dirt or shavings in between the threads. I could see that the sensor was kind of loose but it didn’t want to turn any more. I sprayed some WD40 on it and kind of moved it back and forth with my hand without using any tools. Eventually, it started turning easily and came right out. Installing the new sensor was a breeze. The new sensors come with anti-seize compound already applied to the threads. But, I went ahead and rubbed a thin layer on just to be sure. I was careful to not use too much and not to get any on the sensors. I had bought the silver looking anti seize compound from an auto store a while back for a brake job. It’s pretty cheap and you can almost buy it from any auto store. The sensor on bank 1 turned loose easily and came right out without any problem. I was able to install the new sensor relatively easily as I described earlier using the SSTs I put together. I would say once I had the parts and the SSTs made the entire operation took around 30 minutes.
Conclusion…
I must say that I felt pretty good about the whole thing. All seems to be well and the check engine light has stayed off. What is the next project? Well…I need to do some work on the front spring/shock assembly. There is some thumping and rattling going on while driving over bumps, even little bumps, or just turning the wheels.
Until then...
Kauz
Getting the error code…
A couple of days later, I took the car to AutoZone and they read the error code for me free of charge. They do this as a courtesy and betting that once you know the cause you may buy any malfunctioning sensors from them. So, even though I wasn’t sure if I wanted to try to fix it myself, I figured if I knew what the problem was then I would know what to expect when I took my car to the shop.
Anyway, the error code was P0135 indicating that the heated oxygen sensor 1 on bank 1 was not functioning properly. After reading the code, the guy at AutoZone offered to show me exactly where the sensor was and I accepted his offer. So we popped up the hood and he said “That’s it! Right there!” pointing to the O2 sensor on the exhaust manifold between the radiator and the engine. (You’ll see later that the sensor he showed me was for bank 2 and not bank 1.) After we walked back into the store to print out the error code, he also looked up the price on the O2 sensor and it was around $118 for a Bosch sensor. I thought to myself, that sounds reasonable, but I wasn’t ready to buy the part yet. I thanked him for his help and drove back home to do my research.
O2 Sensor vs Air/Fuel Ratio sensor...
As far as I know only the California models use the Air/Fuel Ratio sensor. No, the O2 sensor is not the same as the Air/Fuel Ratio sensor. The O2 sensor provides a simple too lean or too rich information to the ECM. It acts like a switch it either swings the lean or the rich way and operates in a narrow range. The boundary between the lean and rich condition represents the ideal air/fuel ratio of 14.7:1. The ECM therefore constantly adjusts the air/fuel ratio by a very small amount back and forth to stay at this ideal boundary. The air/fuel ratio sensor on the other hand operates over a wider range and provides a more accurate near linear voltage representing the amount of oxygen in the exhaust. Therefore, with an Air/Fuel Ratio sensor the ECM is able to more precisely control the air/fuel ratio. Also, the Air/Fuel ratio sensors operate at a higher temperature around 1200F (650C), whereas the O2 sensors operate around 750F (400C). And, yes the Air/fuel ratio sensors do cost more, roughtly about 40% to 50% more.
Locating the O2 sensors…
After doing a little search on this site, I found out that my 1997 ES300 has three O2 sensors, sensor 1 bank 1 is located right after the exhaust manifold close to the firewall, sensor 1 bank 2 is right after the exhaust manifold by the radiator, and finally the downstream O2 sensor is located on the exhaust pipe after the catalytic converter underneath and toward the center of the car. Sensor 1 bank 1 is the hardest to find and get access to, but with a shop light and a little persistence I was able to find it. There is really no easy way to get to it though because it’s sort of sandwiched deep down below, between the firewall and the back side of the engine. But, I will tell you later how I got to it.
Buying the O2 sensors…
I know that everybody has his or her opinion on this, but I like to buy factory and OEM parts for most repairs, unless it’s an expensive part and the price differential between the OEM and the after market part is too much. Fortunately, with a little bit of online search I was able to find the O2 sensor (part number 89465-33180 superseded by 89465-06100) from an out of state Lexus dealer for about the same price (whole sale price) as what AutoZone wanted for their Bosch part. The catch was that I had to order the part online from their site to get that price. This was hard to believe! The OEM Lexus part cost the same as the Bosch part from AutoZone? My local dealer had quoted me close to twice that price on the phone. I knew that I had struck gold. At that price, I went ahead and ordered two of them. I figured at 120K miles, the other sensor is probably on its last leg out anyway. Now, when I ordered the part form Lexus, I had to specify whether I wanted the front or rear sensor. The front (upstream) sensor is the one used for sensor 1 on bank 1 and bank2. The rear sensor (89465-06020) is the downstream sensor after the catalytic converter, which I elected to not replace.
Replacing the O2 sensors…
OK, now I have the parts but will I be able to finish the job. Truthfully, before I ordered the parts, I spent about an hour locating the sensors on the engine and deciding how I could get to them. The O2 sensor on the exhaust manifold of bank 2 is by the radiator, sticks out like a sore thumb, and is pretty easy to get to. The bank 1 O2 sensor is however a totally different story. After a long few minutes of looking around with the shop light I spotted the sensor on bank 1, but I could see that there was no way I could get to it from the top of the engine without removing the intake manifold. So I put the car on ramps and got under the car to take a look. Again, I was able to see it from underneath the car but I was having trouble getting my hand through the cracks between the parts and reach it. After laying on my back under the car for a while and wondering why in the heck I am doing this, suddenly I saw a way from behind the suspension cross member that I thought I could drop a socket on the sensor. Well I thought I’m half way there, but the sensor connector was another 10 inches or so higher on the side of the engine and I could not get my hand or fingers through to reach it. There were two problems. First I had to unlatch the tab on the side of the old connector and disconnect it. Second, I had to be able to insert the connector of the new sensor into its place. After scratching my head for a while (kind of tough to do while you’re under the car on your back), I thought I could perhaps use a long flat head screw driver with a narrow blade to undo the latch with one hand and then tug on the wires with the fingers on my other hand to pull the connector out. Well, why not. I thought it would work. Now, I needed a way to be able to lift the connector of the new sensor and to guide it into the mating connector on the side of the engine. For this I needed to build an SST (Special Service Tool). While looking around the garage, I found a spiral looking wire in the trash can which had a glass butterfly on it. I think it was something that you stick in a plant pot. My wife had thrown it away and it seemed to be just what I needed for my SST. I was thinking about using a wire hanger but I could not find one around the house (all the ones we had were plastic), and this thing whatever it was seemed to be perfect for the job. So using pliers I formed the end of the wire into a three-sided square (is that possible?), leaving one side open to get the square around the neck of the connector. I made it just the right size so that I could easily get it around the lower and smaller part of the connector. Now, I could use this to lift the connector and place it in position but my SST wire would be too flimsy to push the connector in. This wasn’t too big of a deal because once the connector was in place I could then use a long screw driver to push the connector in.
The tools for the job…
Here are some pictures of the tools that I used.
I got the O2 sensor socket from AutoZone. It’s a special deep socket with a slit (opening) on the side. The wire at the end of the sensor can be bent down gently and routed through this slit so that it doesn’t get crushed by the end of the socket. I could have bought this socket for around $11, but I got it from AutoZone on a loaner basis. I could return it when I was done for a full return of my deposit. However, I think that I am going to just keep it.
Replacing the O2 sensors…
First of all, I disconnected the negative cable from the battery and tucked it away. I’ve read that if you don’t, there is a remote possibility that the airbags could get deployed while you are working on the car. This could result in possible injuries and at the very least would cost a lot of money to fix. I replaced the sensor on bank 2 first, since it was the easier one to get to. It didn’t take much force to loosen the sensor. However, after about half a turn, the sensor would not turn any more no matter how much force I applied. It seemed as if there was some dirt or shavings in between the threads. I could see that the sensor was kind of loose but it didn’t want to turn any more. I sprayed some WD40 on it and kind of moved it back and forth with my hand without using any tools. Eventually, it started turning easily and came right out. Installing the new sensor was a breeze. The new sensors come with anti-seize compound already applied to the threads. But, I went ahead and rubbed a thin layer on just to be sure. I was careful to not use too much and not to get any on the sensors. I had bought the silver looking anti seize compound from an auto store a while back for a brake job. It’s pretty cheap and you can almost buy it from any auto store. The sensor on bank 1 turned loose easily and came right out without any problem. I was able to install the new sensor relatively easily as I described earlier using the SSTs I put together. I would say once I had the parts and the SSTs made the entire operation took around 30 minutes.
Conclusion…
I must say that I felt pretty good about the whole thing. All seems to be well and the check engine light has stayed off. What is the next project? Well…I need to do some work on the front spring/shock assembly. There is some thumping and rattling going on while driving over bumps, even little bumps, or just turning the wheels.
Until then...
Kauz
Last edited by Kauz; 02-05-07 at 07:29 PM. Reason: new photo link
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Jrb2u (06-10-22)
12-28-06, 08:41 PM
#2
Lexus Champion
Firstly...Welcome to the club.
......and secondly.....this was a very interesting story that I read completely.....and thirdly......I love to read about people who are persistent and thorough when doing a job that you just did. Congratulations!! 
......and secondly.....this was a very interesting story that I read completely.....and thirdly......I love to read about people who are persistent and thorough when doing a job that you just did. Congratulations!!
01-01-07, 08:13 PM
#4
Driver School Candidate
Thread Starter
Firstly...Welcome to the club. ......and secondly.....this was a very interesting story that I read completely.....and thirdly......I love to read about people who are persistent and thorough when doing a job that you just did. Congratulations!!
Happy New Year to All!
Kauz
03-13-08, 08:13 PM
#5
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I did this on Sunday. Thanks for your post which helped me on where the Bank 1 sensor was reachable. Some hints: It takes a bit of patience to locate the sensor since it's covered by a lot of stuff and barely visible. Next, use the O2 sensor socket that you can borrow from Auto Zone. It's the right length that with perhaps a one inch extension, you can fit your rachet into the space. It takes a lot of patience to get the sensor out, due to the very small space and to screw in the new one. I had bought a 02 socket from O'Reilly's and it is longer than the one you can borrow from Auto Zone. It ended up not working, because of the limited space from the distance of the socket to where the racket fits on. You are basically lining the new sensor up and starting it by touch, since you really can't see where it is going in. I ended up not using the homemade SST. My problem was controlling the connector which I could not do well with the SST I made out of a coat hanger. You have to have the right side of the connector going in where it catches (where you put the end of the screwdriver to release it). I used a flexible retrival tool that looks like this:
http://www.amazon.com/KD-2391-Flexib.../dp/B00004SQ36
I actually borrowed my friend's tool. You can get these at most auto parts stores. That gave me the contol to get the correct side iof the connector into the other connection. Be careful when you then push with the screwdriver to finish connecting it. There are lots of sharp edges and if you hand slips, you will end up with a nice sliced up finger with band aids and liquid bandage like me. Patience and a few beers and you can do it.
http://www.amazon.com/KD-2391-Flexib.../dp/B00004SQ36
I actually borrowed my friend's tool. You can get these at most auto parts stores. That gave me the contol to get the correct side iof the connector into the other connection. Be careful when you then push with the screwdriver to finish connecting it. There are lots of sharp edges and if you hand slips, you will end up with a nice sliced up finger with band aids and liquid bandage like me. Patience and a few beers and you can do it.
Last edited by rje; 03-13-08 at 08:18 PM.
03-13-08, 11:59 PM
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I still need to do this 
http://sr1.clublexus.com/forums/showthread.php?t=341375
I gave up looking for it the other day.Ill try again later.
http://sr1.clublexus.com/forums/showthread.php?t=341375
I gave up looking for it the other day.Ill try again later.
04-20-08, 09:29 PM
#7
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Where is this sensor???
So I have read the original post which has given me a lot of confidence to fix my 2000 Es300 air fuel ratio sensor. What I don't understand is why the Lexus dealer wants to charge me $400 for the part and labor when the part is only $206. They are factoring in 2 hours of labor to install the bank 1 sensor 1 air fuel ratio sensor. If I understand correctly this is the first easily visible sensor coming off the exhaust manifold in the front by the radiator? Are they trying to rip me off by charging me 2 hours of labor for something I could order and easily install with that special tool I can borrow at autozone???? Please tell me if this is as easy as it seems. Thanks in advance.
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04-21-08, 06:39 AM
#8
Super Moderator
Actually, bank 1 sensor 1 should be on the rear behind the engine block. That part and labor seems a bit high. You could probably find a knowledgeable mechanic to deal with it, it ain't rocket science.
05-12-08, 01:20 AM
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brilliant article
I wish I had stumbled upon this site and read this article before spending exorbitant amounts on this repair.
I had the engine light come on and drove for a long time without really noticing any difference in performance. I figured, probably just a bad sensor, I'll do it in time.
Then came the CA smog requirement with my registration renewal. I figured, ok they will probably give me the code when I take the test.
I passed the emissions, but failed the "functional" test (engine code P0135).
They offered me this program where I would have up to a $500 CAP (minus $100 deductible max OOP ) credit from the state to get the repair. I figured great, its a win-win situation, cuz my hands are for cuttin' not greasin'.
They made me pick an auto shop from their list. I chose Bowen's Auto Service in La Mesa, CA, because in was close to my job.
Anyway, to make a long story short, the mechanic said it should be no problem and quoted me $207 for what I thought was to replace the sensor.
They replaced it all right, to the tune of $456.79.
($165 parts + tax +, $279 labor [includes unnecessary redundant diagnostics]
To make matters worse, while it made the engine light go off, it caused the car to fail the emissions test.(NO went up, HC went down). They said now that my car was running less lean, it was producing more emissions.
Then they said I would need to purchase a new Catalytic converter!
The OEM cost estimate = $1,500
Or I could opt for a universal Cat =$300, but no warranty and only an estimated lifespan of 2 years.
Since my deductible only applied to a $500 max limit, I would have to cough-up over $400 OOP
Has anybody ever heard of this before?? What else could be going on? Should I replace all the O2 sensors to be sure? Everything was fine just 2 years earlier. They said Cats have only a 10 year lifespan; Is that true? Its a 1997 Lexus 300 ES with 125K miles, and otherwise perfect running condition.
If you ask me, this is just another example of failed democratic government policies....good intentions, bad results, and more cost to the consumer in the form of enrichment of auto repair shops and questionably fraudulent charges.
I had the engine light come on and drove for a long time without really noticing any difference in performance. I figured, probably just a bad sensor, I'll do it in time.
Then came the CA smog requirement with my registration renewal. I figured, ok they will probably give me the code when I take the test.
I passed the emissions, but failed the "functional" test (engine code P0135).
They offered me this program where I would have up to a $500 CAP (minus $100 deductible max OOP ) credit from the state to get the repair. I figured great, its a win-win situation, cuz my hands are for cuttin' not greasin'.
They made me pick an auto shop from their list. I chose Bowen's Auto Service in La Mesa, CA, because in was close to my job.
Anyway, to make a long story short, the mechanic said it should be no problem and quoted me $207 for what I thought was to replace the sensor.
They replaced it all right, to the tune of $456.79.
($165 parts + tax +, $279 labor [includes unnecessary redundant diagnostics]To make matters worse, while it made the engine light go off, it caused the car to fail the emissions test.(NO went up, HC went down). They said now that my car was running less lean, it was producing more emissions.
Then they said I would need to purchase a new Catalytic converter!
The OEM cost estimate = $1,500
Or I could opt for a universal Cat =$300, but no warranty and only an estimated lifespan of 2 years.Since my deductible only applied to a $500 max limit, I would have to cough-up over $400 OOP
Has anybody ever heard of this before?? What else could be going on? Should I replace all the O2 sensors to be sure? Everything was fine just 2 years earlier. They said Cats have only a 10 year lifespan; Is that true? Its a 1997 Lexus 300 ES with 125K miles, and otherwise perfect running condition.
If you ask me, this is just another example of failed democratic government policies....good intentions, bad results, and more cost to the consumer in the form of enrichment of auto repair shops and questionably fraudulent charges.
Last edited by huesero; 05-12-08 at 09:27 PM. Reason: correction emissions
05-13-08, 07:47 AM
#12
Super Moderator
A few things come to mind:
1. If you are running lean you may have some injector blockage (fuel injector cleaner)
2. See the condition of the coolant (also where is the engine temperature gauge at?)
3. Check to make sure all hoses related to the evap system are hooked up with no cracks on any of the hoses. (this is key and can account for 1/3 of the NO). A code should realistically come up, an OBDII code in the P040X range.
4. Examine the exhaust manifolds to make sure there are no cracks.
Finally the cat. Replacing it (I am figuring that if it is anything it would be the main one below the vehicle, as opposed to one of the two precats off of the exhaust manifold) would help eliminate roughly the other 2/3rds of your NO.
There are cat codes, generally the P0420, but I can tell you from my experiences living south of the border for 6 years, where this code is VERY common, that sometimes one can have a bad cat and the code will not light up on an OBD2 vehicle.
The universal cats, particularly those of Magnaflow like I have, work much better than OEM.
1. If you are running lean you may have some injector blockage (fuel injector cleaner)
2. See the condition of the coolant (also where is the engine temperature gauge at?)
3. Check to make sure all hoses related to the evap system are hooked up with no cracks on any of the hoses. (this is key and can account for 1/3 of the NO). A code should realistically come up, an OBDII code in the P040X range.
4. Examine the exhaust manifolds to make sure there are no cracks.
Finally the cat. Replacing it (I am figuring that if it is anything it would be the main one below the vehicle, as opposed to one of the two precats off of the exhaust manifold) would help eliminate roughly the other 2/3rds of your NO.
There are cat codes, generally the P0420, but I can tell you from my experiences living south of the border for 6 years, where this code is VERY common, that sometimes one can have a bad cat and the code will not light up on an OBD2 vehicle.
The universal cats, particularly those of Magnaflow like I have, work much better than OEM.
05-13-08, 11:23 AM
#13
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Orale
That was good advice, I checked the coolant and the hoses, and the temp has been normal. Manifold is intact. But check this out....
I took it down to Cuyamaca college and had them run another test.
Low and behold, it passed!
The emissions were:
HC = 52
CO = 0.05
NO = 141
Im thinking como es eso, that is really strange, huh?
I dont know what to think. Either they forgot to clear the memory of the fault code and driving it around with the new sensor made it reset somehow. Or the mechanic was trying to make money off of selling gatos.
I took it down to Cuyamaca college and had them run another test.
Low and behold, it passed!
The emissions were:
HC = 52
CO = 0.05
NO = 141
Im thinking como es eso, that is really strange, huh?
I dont know what to think. Either they forgot to clear the memory of the fault code and driving it around with the new sensor made it reset somehow. Or the mechanic was trying to make money off of selling gatos.
06-23-08, 10:53 PM
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hey guys i recently had a P0135 trouble code come out..so i bought a new O2 sensor (bank 1 sensor 1) from an autoshop and installed it. i had the check engine light cleared at Autozone, and all seemed fine for the first week. Then today, i turned on my engine and the check engine light turned on again. I checked the code and it was P0135 again! What do you suppose the problem could be? I'm pretty sure I installed the new O2 sensor properly. Is there a possibility that the same trouble code appeared (P0135) when the problem is coming from somewhere else?